Second-half strikes from Mohamed Salah and Marco Streller cancelled out Oscar’s opening goal to extend Chelsea’s winless run in all competition to four matches.
The Blues currently occupy sixth place in the Premier League and are three points behind early pacesetters Liverpool and Cahill believes three points tomorrow can be the only remedy to their faltering start.
“It’s a big shock really,” said the 27-year-old, capped 18 times by England. “It’s not a disaster, but it’s not ideal.
“A club like this wants to win the majority of games it plays. That’s the expectation. It’s a blow but it’s not the be all and end all.
“We need to win our next game now, as simple as that. We’ve got the squad to do it, we need to go on now and get back to winning ways on Saturday.
“The onus was on us to step it up [against Basel] and we didn’t quite do that. At this sort of level we get punished and we’re obviously disappointed.
“We played against them twice last year and they’re a very good side. We gave them a bit too much room all over the pitch but in the first half we looked like we were in control. In the second we didn’t quite step it up.
“We knew we could go up a level, but we didn’t do that and that’s what cost us the game.”